The idea of saying bless you after a sneeze started during the bubonic plague epidemic of the sixth century, when Pope Gregory the Great would say, “May God bless you,” to those who would sneeze. His intentions were to wish Gods blessing onto those who sneezed because it was a sign they had the plaque. At that time, having the plaque was almost a sure sign of death because of the limited knowledge of health and disease. Saying may God bless you for a sneeze was the Popes way in hoping that the person who sneezed wouldn’t die.
Saying bless you, or something similar to it, also came from people’s belief that when you sneezed your soul leaves your body. So, to stop the devil from capturing your freed soul, you say bless you. It is also believed that when you sneeze your heart stops, which we know actually doesn’t, and saying bless you is a way to welcome a person back to life. When you sneeze, there is changing pressure gradients in your chest, which also changes your blood flow. Sneezing changes your blood momentarily, but it does not stop your heart.
Some other traditional responses to a sneeze include:
French: “a tes/vous souhaits”………………….to your wishes